Spray guns for paints, lacquers, adhesives or other flowable materials require careful cleaning of the material-conducting areas after each use or before each change of material, if a cartridge, i.e. exchangeable inserts, preferably designed as a disposable item, is not used for material conduction. Such an advantageous spray gun with a handle region and with a head equipped with a cartridge, wherein the cartridge has an inlet area for a material-conducting channel that ends in an outlet area and wherein the inlet area of the cartridge is or can be connected to a supply container for the material to be sprayed and wherein the cartridge preferably guides at least one material-conducting component of the spray gun, is known from DE 3016419 C2, for example. This spray gun has a divided head with an area at the rear and an area located at the front in the spraying direction. The rear end of the front area of the divided head is equipped with a plug-in receptacle for a cartridge having a tubular material-conducting channel extending in the spray jet direction, in the interior of which a nozzle or paint needle is arranged. The nozzle can be moved backward and forward in the spray jet direction by means of a lever and spring mechanism, so that the material to be sprayed can pass through a nozzle arranged in the outlet area for processing. The cartridge is retained in the head by means of plug pin connections. After use, the pin connections can be detached, the two head areas can be folded apart from one another, and the cartridge including the paint needle can be removed from the head and can then subsequently discarded. Then a new cartridge can be mounted on or in the spray gun. Cleaning the material-conducting areas of the spray gun is unnecessary in this case. The pin connections are relatively complicated, however, difficult to create and release and also do not always guarantee problem free operating safety.